From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D0008C433F5 for ; Mon, 3 Oct 2022 21:46:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229723AbiJCVqb (ORCPT ); Mon, 3 Oct 2022 17:46:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58562 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230002AbiJCVqC (ORCPT ); Mon, 3 Oct 2022 17:46:02 -0400 Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 69B0A20BF5 for ; Mon, 3 Oct 2022 14:45:24 -0700 (PDT) Received: by mail-pj1-x104a.google.com with SMTP id y16-20020a17090aa41000b001fdf0a76a4eso5057821pjp.3 for ; Mon, 03 Oct 2022 14:45:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date; bh=wyqNJEpK8hc99eBxWvCga97s0cP9TToGQQczW693ZQg=; b=h8czXoK277slpGQf+bpvwfua+gFDF9NUzYgIFFOEfmpYpF8o1tAD/fMdDL7197AECO THvbVgyzmJynlB+rrpjAGhEKfhe9Bw6gD9Bks5W4EOOOf7EUMA0tzBUKiVJJcfxtM7K6 rCMsuJYVKVVK9jAheJWA6FGDLIkABfqtfuPv4ibUAjr+aSQFC/wyp99fSj+1FtrsKm5I 0FhQMMQI8gPFhzdO54qaj6Nh0pMyr58ioMFEGdDYOkDOvXqIX6zA3prnyeKAlivv9XsC iBHQ4EP3+NwiGdGBfj3mb+s4fc1mi6HjC8UTwx9MVWitByDPwAO7pyRcSDtIHDY2B3q0 c2fA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date; bh=wyqNJEpK8hc99eBxWvCga97s0cP9TToGQQczW693ZQg=; b=AguMcZvXvwNTog+HQhwEZ6KyBp40cF+mQOsB6RmO677bcjQFemtxmFQgMPpUOlzjEX MKZH6d1OjDObrXTqxouIdJ7Q+dGEGFPhMHzvuxWpFJUbY/bYDgeTfqibp9L1GX8A2Pej M5uq7/20gPBLolC2uDloVlMNCSxLlIpVEaiqLZjs3twr9ZgQAjDZpWwoFshcvmsH9/+E Axz69ABW6pALaLCAuteeTRmYTgiwAb1+iP/T5FM2JhZWjEk4czQMadCM6EOEDVKVnmTE 4lbKO8sfZpBAvES0FeERZa1Giaq9yu6m2GWMdfAf+SfQEFKh4S/gAxx+aMgtn2D6fb8E GO6Q== X-Gm-Message-State: ACrzQf1OHebBDM6pXI/wYOu9aB7ckO/z4BuKlaVbtznTdeZf7Sjx6w// C6QWJ/YzDAlTp51mNSJGm6LcKRfkfaUKlLXH3LijPOTlBKKmvnxSyn4pKR3RENOZ2JiMxVjRIbc hjhTgpaj0LPlgQ57hEPNv2c7I+BclWAkfy0u1raFAMkJjfWhwQ9qClBjLy8sthq2KIe0ug48I X-Google-Smtp-Source: AMsMyM4btjRP5nxnP96+XjlgNpxrr4Brvn4C5nCpYv1pEtkw8lHkLuZn9LJAO50hz9iyuzqpA1Qd00v0wzqq X-Received: from connoro.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:a99]) (user=connoro job=sendgmr) by 2002:a17:90b:3ec9:b0:205:cc2d:7fb6 with SMTP id rm9-20020a17090b3ec900b00205cc2d7fb6mr13833913pjb.142.1664833523279; Mon, 03 Oct 2022 14:45:23 -0700 (PDT) Date: Mon, 3 Oct 2022 21:45:01 +0000 In-Reply-To: <20221003214501.2050087-1-connoro@google.com> Mime-Version: 1.0 References: <20221003214501.2050087-1-connoro@google.com> X-Mailer: git-send-email 2.38.0.rc1.362.ged0d419d3c-goog Message-ID: <20221003214501.2050087-12-connoro@google.com> Subject: [RFC PATCH 11/11] locktorture: support nested mutexes From: "Connor O'Brien" To: linux-kernel@vger.kernel.org Cc: kernel-team@android.com, John Stultz , Joel Fernandes , Qais Yousef , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider , Will Deacon , Waiman Long , Boqun Feng , "Paul E . McKenney" , "Connor O'Brien" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quick hack to better surface bugs in proxy execution. The single lock used by locktorture does not reliably exercise proxy exec code paths for handling chains of blocked tasks involving >1 mutex. Add 2 more mutexes and randomize whether they are taken. Signed-off-by: Connor O'Brien --- kernel/locking/locktorture.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c index 9c2fb613a55d..bc3557677eed 100644 --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -48,6 +48,8 @@ torture_param(int, stat_interval, 60, torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable"); torture_param(int, verbose, 1, "Enable verbose debugging printk()s"); +torture_param(int, nlocks, 1, + "Number of locks"); static char *torture_type = "spin_lock"; module_param(torture_type, charp, 0444); @@ -327,6 +329,8 @@ static struct lock_torture_ops rw_lock_irq_ops = { }; static DEFINE_MUTEX(torture_mutex); +static DEFINE_MUTEX(torture_mutex2); +static DEFINE_MUTEX(torture_mutex3); static int torture_mutex_lock(int tid __maybe_unused) __acquires(torture_mutex) @@ -666,6 +670,7 @@ static struct lock_torture_ops percpu_rwsem_lock_ops = { */ static int lock_torture_writer(void *arg) { + bool twolocks = false, threelocks = false; struct lock_stress_stats *lwsp = arg; int tid = lwsp - cxt.lwsa; DEFINE_TORTURE_RANDOM(rand); @@ -677,6 +682,12 @@ static int lock_torture_writer(void *arg) if ((torture_random(&rand) & 0xfffff) == 0) schedule_timeout_uninterruptible(1); + twolocks = nlocks > 1 ? (torture_random(&rand) & 0x1) : 0; + if (twolocks) + mutex_lock(&torture_mutex2); + threelocks = nlocks > 2 ? (torture_random(&rand) & 0x2) : 0; + if (threelocks) + mutex_lock(&torture_mutex3); cxt.cur_ops->task_boost(&rand); cxt.cur_ops->writelock(tid); if (WARN_ON_ONCE(lock_is_write_held)) @@ -691,6 +702,11 @@ static int lock_torture_writer(void *arg) WRITE_ONCE(last_lock_release, jiffies); cxt.cur_ops->writeunlock(tid); + if (threelocks) + mutex_unlock(&torture_mutex3); + if (twolocks) + mutex_unlock(&torture_mutex2); + stutter_wait("lock_torture_writer"); } while (!torture_must_stop()); @@ -830,11 +846,11 @@ lock_torture_print_module_parms(struct lock_torture_ops *cur_ops, const char *tag) { pr_alert("%s" TORTURE_FLAG - "--- %s%s: nwriters_stress=%d nreaders_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n", + "--- %s%s: nwriters_stress=%d nreaders_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d nlocks=%d\n", torture_type, tag, cxt.debug_lock ? " [debug]": "", cxt.nrealwriters_stress, cxt.nrealreaders_stress, stat_interval, verbose, shuffle_interval, stutter, shutdown_secs, - onoff_interval, onoff_holdoff); + onoff_interval, onoff_holdoff, nlocks); } static void lock_torture_cleanup(void) -- 2.38.0.rc1.362.ged0d419d3c-goog